Various solving strategies in probability of events could complicate the students in choosing the best strategy in problem solutions. This research was carried out to identify the favourite solving strategies used by college students to solve probability and event problems. As a preliminary of a case study, only three students were selected as participants. In this study, the participants have learnt the probability topic in secondary schools as they must apply the knowledge in college level. Think aloud analysis was used to evaluate the influence thought and behaviour of the participants when solving the task. An in-depth semi-structured interview was conducted together with the think-aloud analysis to gain rich and thick descriptions from the participants. Protocols were coded and analyzed to determine the strategies used and the reason of choosing those strategies to solve the problems. Results indicated that participants loved to use tree diagram as solving strategies in solving probability problems without knowing the accuracy of its effect. Therefore, educators can plan strategies, set problems, or prepare activities for students to understand the probabilistic situation and probabilistic reasoning to solve problems. Otherwise the students are merely copying procedures presented in class.